If you can get it for a good price then it will work, but it's way overkill.
Only 100 feet you don't really need to worry about voltage drop because you are not far enough away for too much drop. The MEP-003a is rated at 52 amps if you are using the 120/240 configuration like you should be for a house.
The first thing you need to figure out is if it's going to be buried or above ground? Lying on the ground or strung overhead? For above ground uses, strung overhead you can get some aluminum service entrance cable suitable for 60 amps, don't remember right off the top of my head, but I'm going to say it would probably be 4 awg possibly 6 awg.
If it were lying on the ground and you were going to string it out only when needed, I would buy some 6/4 type "SO" cord (6/4 means #6awg 4 conductor). It's rubber and waterproof, tough stuff and very durable.
Underground you'll want 60 amp "UF" cable. The "UF" stands for underground feeder cable. It's rated for direct burial and isn't terribly expensive.
No matter what route you're going to use, you can probably get away with #6 awg since it's typically rated for 60 amps.
Also, no matter what you use, In your situation, you really should use 4 conductors because you said you had a secondary panel...meaning your ground and neutral wire should be isolated. So you should run 2 hot wires from the genny, one neutral from the genny and a separate ground that also grounds the genny.
If you are not 100% comfortable doing the wiring on your own or are not sure about what kind of wire or size to use. Or how to make the hook up's. Do yourself a favor and hire an electrician to do it for you. It'll get done right and your unburned house will thank you for it. Just my