After looking at the details I think it's better to go with Legends chem. There are a few AM players I would not want to use and to be forced to use all of them to get some +1's that I get with Legends chem anyway basically, is not worth it. Already gonna get +1's and +3's on Deion from Legends chem and Strat cards.
The honest truth is, if you can acquire all All madden release 2 cards. your team doesn't need 91 OVR cards. Unless you are a die hard John Madden fan who just really wants All Madden cards
The only 89 AM cards that I use really , just limited to LT and he's a backup (big Giants/LT fan)...so what's the point of boosting 89's to 91's when they won't start anyway. Okoye and Csonka will still start over Alstott. Ed Reed over Lott. Metzelaars, Pitts, Casper, Delanie, will all start over Tony G. Matthews might start at LG but McDaniel is fine there. There's a ton of MLBs better than Mills, even with a +2 boost. Montana won't start over Elway. Moss might make the starting 5 but Carmichael, Megatron, Hester in the slot, B Marsh, Plax...too many top WRs for a 91 Moss to really make a difference. Sapp is good , always plays well in MUT but there's Seymour with 0 AP defensive rally, Mean joe, Fridge, etc....Bruce Smith - I mean, there are a ton of DEs who are better than a 91 Smith.
I get what EA is trying to do, having an AM TT but I personally think it was poorly executed.