As far as I'm concerned, TTS is the right way to play the first MGS game. Much better gameplay, and they offer you the option to play it as the original if it bugs you that much.
Personally the only bad MGS game I've ever played was Peace Walker. Complete step back from Portable Ops.
Opinions and all, but how can anyone think this? I own both games on psp, and PW is leagues better than PO. PW took some of the aspects of PO, improved them while trimming away the fat.
List of PO problems
Horrendous controls.
Bland maps. I mean disgustingly bland.
Piss easy/forgettable boss fights.
The worst writing of any Metal Gear game ever. Seriously, it's BAD.
Annoying soldier recruitment system.
Shitty interface and menu music.
Peace Walker is MUCH better than this game. By a mile. I'd rather fight mech after mech after mech than even attempt to beat Portable Ops again.