It's hard to give advice when you don't know exactly how a person uses their phone or what features are higher priority to them.
They both have 1GHz processors, pretty decent cameras, and run 2.3.5 Gingerbread. The Warp has about 1GB more of available internal space than the Marquee. The Warp's screen is 0.3" larger at 4.3" than the Marquee's at 4.0". The Marquee, however, has the super bright screen. It also boasts HD video. The Marquee was previously released as a postpaid contract phone on Sprint last year.
For me, personally, I never really shoot video with my phone and, while the smaller, brighter screen would have been nice (I have very tiny hands), it wasn't nearly close to being enough for me to justify spending the $100 difference in the price tags.
Does the Warp have some quirks? Yes, all smartphones do. Is it a great phone for the price you pay? I think it is.
You may also want to check out the many YouTube videos comparing the two devices.