As of right now, I'd say your best options are Takara's Masterpiece-09 Rodimus Convoy & Fansproject's TFX-04 Protector set.
VS 
Frankly, it depends on what you look for in a collectible- what you value. In this case, it's design VS durability.
So far, I've read many cases of the MP-09 being very sensative and prone to breaking- which means it's mostly a display piece.
I even bought the Hasbro version myself and it broke WHILE I was removing it from the box- and keep in mind, I was being as gentle as I could possibly be.
It doesn't matter if you buy the Hasbro or Takara version- it's still just a very sensative toy and you need to be extremely careful with it.
The pros of the MP-09 Rodimus Convoy:
1) It's the closest representation of the G1 character design.
2) It's got a matrix cavity in it's chest, and a decently detailed Matrix of Leadership.
3) It has 2 vehicle forms, both equally accurate to their G1 vehicle mode designs.
4) It's big and can pull off many impressive poses.
The cons of the MP-09 Rodimus Convoy:
1) It has extremely thin plastic in a number of places, making it brittle and capable of being easily broken.
2) The matrix it's provided with, is far too small for it to hold- plus it doesn't even open up.
3) Because of it's "back kibble" in robot mode, it's been known to have poor balance and easily tip over.
The Protector Upgrade Set is a safer choice, in my opinion- because it hasn't been known to break AND it's cheaper.
The pros of the Protector Upgrade Set:
1) It's a new design, with some rather flashy paint applications and flame molds.
2) I haven't heard any cases of this set breaking- so it's durability is good.
3) It comes with a "handshake" piece, to use with Classics Optimus Prime.
4) It's vehicle mode is sleeker and looks more futuristic.
5) It comes with a small comic book, showing Hot Rod's upgrade to Rodimus Prime.
The cons of the Protector Upgrade Set:
1)It requires Classics Hot Rod- in order to complete and form Rodimus Prime.
2) It's pieces have been known to become loose and pop off during play- but that was only in a couple reviews I read.
3) It's posability isn't as great as the MP-09's.
4) It's much smaller than the MP-09.
5) It doesn't have a Matrix of Leadership.
Overall, my suggestion would be the Protector Upgrade Set- because it's cheaper and safer in terms of breaking.
It depends on whether you're all about design and flashy collectibles, or strong, durable ones- that you can fumble and play with, without risking any functional or cosmetic damage.
My vote: Fansproject's TFX-04 Protector!
