Hello,
For what it's worth, I was in your predicament just about 1 month ago. I was considering the Fender Deluxe III or the Mesa 5:50. This is what it boiled down to for me.
The Fender requires pedals. Period. Really, when you get right down to it, unless you're going to play clean only (which is fine), you are going to be forced to get pedals as soon as you want to get a decent burn out of the amp. No Fender is going to compete with a Mesa amp in the dirty sound. Ok, so in reality, it a Fender and pedal combination or a Mesa amp on its own.
By all means, the Fender/pedal combination is great and you'll love it I'm sure, but consider this... The Mesa amp will do it all and do it all very well. The cleans are so clean that I now prefer to play my acoustic guitar through it and I hardly use my Crate Gunnison anymore. The Crate amp sounds very nice, but the Mesa 5:50 clean channel just gives you a beautiful sound. Then you can put the Mesa into Crunch, Blues or Burn and you change the animal each time.
But for me, the real final straw was the 5 or the 50 watt setting. In 5 watts, you can really dig into the 6L6's (or EL84's in the case of the 5:25) and clearly hear the breakup. It's hard to describe, but when you hear it, you know it. I find myself tearing into the G chord over and over. It drives my wife nuts because the louder I play it, the more it breaks up and the wider my smile gets. It's a sound you just can't beat. That Fender you're looking at will do that too, but it will have to be set so freak'en loud, you'll end up blowing your ears out in the process. The Mesa will do it at bedroom volume levels (although I think my wife would disagree with that). Put it in the 50 watt setting and the crowd will hear it too. It’s shockingly loud and SO clean sounding through its volume range. Impressive in its own right.
Anyway, I went with the Mesa Express 5:50 2X12 and could not be happier. My objective is to master the amp (and guitar) and learn what the amps real potential is. I have yet to really tap into it. That should take me a few years to do. Then, I will venture into the world of pedals which is really like learning a whole new instrument again. Armed with my experience with the amp and achieving the sound I'm looking for and then having the flexibility of having a multi effects pedal, well, my wife will need some thicker ear plugs!!
Go with the 5:50 or 5:25. Learn the amp, find your sound and then take on the pedals and concur the world.
Good luck.
Adam