Yup.
I run MGT, but the supplements really stink as a whole.
WOW. I feel like the other side of the coin. For me, I found that MGT kind of created a slightly different universe to canon Traveller. Personally I've found the supplement to be superb and havn't bothered with much of the rest. (Take Supplement 3: Fighting Ships for example. 35+ pages of deck plans for the Tigress for example. Simply stunning and very welcome. Also it has 'The Plankwell' deck plans. A rather large couple of undertakings there. I also love the other supplements(in particular the other starship books again for there deck plans). A couple of the adventures are terrific as well.
For myself, I started with the original CT black books that a friend lent me. I really enjoyed them but alas most people in my local area where AD&D freaks(to this day I hate that game because I really wanted to game in space and there was everyone killing off monsters by the score instead... BORING). Years later I purchased the TNE rule book, again experiencing the same issues as when I'd borrowed classic. So I sold that. Then it was without doubt Chris Foss(one of my favourite artists of all time) who painted fantastic artwork all over T4 and I purchased a fair amount of those books and held on to them.
So T4 was my preferred system, mainly because it's a touch different and removes all the rule crunching talk that pops up with other versions.
However, now T5 is upon us, I'll be using that predominantly now. I'm looking forward to the new wave of T5 material to come too.
All that said, once I got the MegaTraveller books, I was really impressed with the material and especially love the Digest Group Publications with my favourite Traveller resource so far being 'The Starship Operators Manual', really well written and worth every cent if you can find a copy.
Don't fear checking out the other systems. There all Traveller in the end and if your happy with CT, just use CT rules with those games, no ones got the laser as they say.