I'm no expert, but I don't see why people still use old school Defiants, MVAE, etcs and not the Chel Grett Warship.

Now I pretty much exclusively play escorts with my Tact toon. Although the Chel Grett only has a 13 turn, with 4/4 front/back weapons and 4 Tact Slots, what's not to love? 1 Sheild Modifier, good hull...

What is it I'm missing. Do people play the others for nostalgia? Or is there something that the T4/T5 variants have that make those better than the Chel Grett?

Thanks for any feedback as I'm really at a loss on why to fly anything else currently available

I think most people prefer to fly Starfleet Ships.

^
This + the 5th Tac console of the Fleet versions of the above mentioned ships !!!

I fly the Chell Grett warship on my KDF tactical but now that i've done the Omega rep may switch back to my B'rel BOP retrofit

There are a number of factors that lead to why a player will chose a ship.

The chel grett is a solid choice for tac captains but under certain circumstances has many flaws as well.

RPers won't fly it as its not a "hero" ship as per ST canon.
Others are PvPers where the shortcomings of the ship become more prevalent.
Or some just think it's ugly and will shy away despite the pros.

The list could go on and on.

Myself as a PvPer won't fly the ship as there are many other escorts with comparable stats with better turn, tac slots, add ons, etc... My favorite escorts are:

Jem'Haddar attack ship
Fleet Defiant
Fleet Multi Vector Escort
Fleet Patrol Escort
Fleet Saber
Steamrunner
Fleet heavy escort carrier
Chimera destroyer

All Good ships and for various reasons I'd pick any of these before the chel grett.

Well, to answer your question you would need to be aware that not everyone has access to a Chel Grett (you could only get one per character by completing the race 25 times over a 35? day period) so that severely limits numbers somewhat.
For those that do have one it is a bit of a Marmite situation... some (myself and 6 of my toons) fly one and love it... others seriously hate it because it does not fit their own playstyle/have enough hull/have enough tac skills/consoles/etc. Don't forget that it also has almost no skin customisation whatsoever (and some HATE its looks with passion).

I have sci, eng and tac toons on fed side and eng and tac toons on the KDF. I had flown the free Odyssey, assault cruisers, star cruisers, mirror patrol escorts, Raptors, mirros Qins, Vor'cha, Negh'var and almost every free sci ship you could.
I found I could change any KDF toon specced for a raptor or mirror qin straight into a chel grett and, whilst they lost a little they gained a LTCOM. sci skill (grav well is a favourite) and they had very similar turn rates, more hull and could load 4 cannons and 4 turrets quite happily.
Even those toons not really specced for an escort/raptor build (my fed sci and first toon, before I learned what the hell I was doing, flew cruisers so was a healbot) fly this beast with ease and things go BOOM a lot. I rarely die, and if I do it is in a fleet defense where the other players are level 30 or below... seriously, that hurts when you draw ALL the aggro in a destroyer
I rolled a new sci on both factions after WWonderland and have had a blast speccing them for the ships they have available (Vo-Quv and Luna) but I would have had just as much fun, I suspect, in a Chel Grett.
If the powers that be ever gave the KDF a K'Vort with the Chel Grett's stats, BOFF layout, turn and everything the same I'd buy it in a heartbeat.

personally i believe the breen cruiser is great, but there are other ships just as good and capable of delivering more dps. i use it on 3 of my 6 chars and each is different, but it also has a few minor disadvantages.*
One disadvantage of it that i see is that a hangar bay is worth more, much more than a rear weapon slot.
The lower turnrate takes practise, and can be a bummer from time to time, but it is not that big of a drawback, atleast not in PVE.

certainly among the top ships currently ingame and designed for the current PVE content, but IMHO the JH bug still beats it statwise.

*one of my tac toons still uses the 9 console guramba, simply because the javeline is that awesome in stfs and anything that is worth being oneshot. You can never dublicate that with the breen cruiser...

I fly it around Defera as it seems the best ship to rescue Defari in. By rescue I do of course mean put out of their misery

May not be the most effective ship but I generally fly sips for there looks anyhow.

Chel is pretty cool, science heavy Battle Cruiser. You're comparing Apples to Oranges, Feds are use to flying escorts, this is a Battle Cruiser, something the KDF are more use to. I have a tac which I'm waiting to lvl that will use the Chel and I appreciate the Battle Cruiser.

Thanks for the great replies.

Really give me something to think about.

I do understand the RP / lore issue. I'm usually big on that too, but have just overlooked it for this ship cause I liked the ship so much.

As for the PVP vs PVE, I could see that too. I don't PvP, so for me (the turn rate especially) in PvE is fine.

Does the 5th slot on the Fleet variant Defiant and MVAE add a lot of firepower? I could get either now, but haven't because I assumed the diminishing returns wouldn't be worth it (and I think they are only 4/3 as opposed to 4/4 front/rear). Therefore, does the 4th back slot sort of equal out the 5th console?