Wow! Talk about irony. I'm actually going to pick up a 5:25+ next year and let my Electra Dyne go. I'll list out some thoughts based on my experiences...
1) I have owned both amps, so I have extensive knowledge of both.
2) The Electra Dyne has better tone, but not significantly better, and the Express is more versatile.
3) If you play at home and have a family, they will hate the Electra Dyne.
With judicious use of the Master control, you can get usable low-volume tones, but it goes from off to loud far too easily.
4) Mesa did a good job balancing the single row of controls for all three channels on the Electra Dyne. I've never really had any complaints about this, except...
5) It's really difficult to adjust clean and dirty volumes! It's stupid to have to reach around the back of the amp to turn a tiny knob to get your volumes to balance. This leads me to...
6) If you get the Electra Dyne, make sure it has the clean/gain trim knob on the back. The amp is unusable without it, in my opinion.
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Here's why I'm switching to the Express: (I say 5:25, but I'm going to compare the 5:25 to the 5:50. If I think the 5:50 is significantly better, I'll get it, though size/weight is one of the reasons I'm going back to the Express.)
1) Size and weight.
I've been lugging the Electra Dyne head around a lot lately, and man, it's big. It looks really cool and sounds great, but it takes up too much space at home and in my CR-V. The weight makes is very cumbersome going up and down stairs, too. I can't imagine owning the combo version of the Electra Dyne!
2) Versatility. The Electra Dyne is great at what it does, but it's limited by only having one set of controls. I'm also not a fan of how the reverb is implemented. I want reverb on my cleans, but not my dirty tones. This is impossible to setup without connecting another footswitch to the amp and tap dancing. The Express has stellar base tones, lots of versatility in the 2 modes per channel, and it has individual reverb controls for each channel. Not to mention, the reverb knobs are on the front of the amp!
3) The Electra Dyne footswitch drives me nuts. I can usually keep track of whether I'm switching between Clean and Vintage Hi or Clean and Vintage Lo, but more than once I've made the mistake of being on the wrong one. The difference isn't huge, but there is a difference. If you're a guitar/amp and nothing else kinda guy, it's not that bad. I love delay in the loop, though, and playing live, it's just one more thing to distract you from the music.
4) Speaking of switching, I don't understand why Mesa didn't design the switching circuit to allow immediate access to all three modes. It's also stupid to have to buy a separate reverb switch. These are obviously just my opinions.
5) While I'll miss the Presence control on the Electra Dyne, the new Expresses have the graphic EQ, and if I had to choose one or the other, EQ wins for me. I'm a Strat player, and I tend to keep the Presence down pretty low anyway.
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So those are some of my thoughts. I don't want to disuade you by any means. No amp will ever be perfect for everyone, and the Electra Dyne, as much as I love it, just isn't the best fit for my life right now. It sounds incredible, though. Even my friend who hates Boogies loves the sound of the 'Dyne. Good luck with your decision, and Merry Christmas to you, too. For what it's worth, you're choosing between a great amp and a great amp. It's hard to make a bad decision.
