All of these Harry Potter / Daigon Alley threads have me kind of considering doing a 4 day at Universal and then 4 day at Disney, instead of the whole trip at Disney. I absolutely LOVE Harry Potter and seeing the pictures is just making me want to go so bad! Now, I'm not looking to open the "who is better" debate.... I already got slammed on another one of those threads!

Just a simple conversation about doing BOTH in one trip. Because I think that BOTH have their value and BOTH are great parks....
For those of you that have done split vacations to each, did you find that you didn't have enough time to give each one? Was it too rushed? Would you start at Universal / finish at Disney? (not because Disney is better... I'm thinking because of ME) We've always just gone to Disney, so I don't know.....

Any feedback would be greatly appreciated. Clearly, we have some time to nail this down, but I have started pricing it out to see how it looks....
What resort at WDW? When we had our first stay at both, we had had a 2 bedroom at OKW (and then a 1 bedroom once extended family left). Then we went to Universal where we had a small room at Royal Pacific, and it felt like we were in a closet.

Royal's rooms are small and OKW is, you know, big.
So if you're going from big to smaller, end with big. (so, WDW)
On the other hand, once you've had unlimited Express Pass, you'll think less of FP, and possibly even less than that of FP+. (as I typed I realized that it's + now, not just FP, and, well, UGH)
On our two-site trips we end with Universal. We tend to have such FUN there that although we would love to stay, we're not SAD to go. We generally really make the most of those visits, both in do-do-do, and in rest and relax. Whereas we are often sad to leave WDW; maybe because we're somehow imprinted on Disney, or, really, for me, because I cannot figure out HOW to have a great trip there. I'm still getting turned around in MK b/c I keep expecting it to have the same footprint as
Disneyland. Anyway, it works out best for us (me) to go to WDW first and then Uni.
As for the two-ticket issue...that's kind of how we ended up with Universal APs. WDW, too, because we were making our trips twice inside of 365 days; we haven't yet had a WDW trip with just tickets, actually. We had one trip to Uni without APs, thinking it was a one time thing just for Harry Potter...and regretted deeply that I hadn't budgeted for an AP upgrade. Went back well inside of a year, had to pay for another set of tickets (I just got the AP, and then DH and DS upgraded before the trip was done with). Renewals are so incredibly reasonable still, for now, that it's simple to just keep them going. (we also tend to book AP rates at the onsite hotels, so it's good to have an AP for that) We do NOT always keep an AP going for WDW, though. That's super-expensive!
Our FIRST trip to Universal was 4 days. Of course, our first trip to WDW was 10. (we went back to WDW after Uni, and that, my friends, was painful b/c of the EP vs FP issue and also because we loved loved loved everything at Uni so much!) We definitely stay for long periods of time when we go on vacation! Or we try to, at least.
Our last trip was 8 nights (portofino club level, oh what luxury) but DS and I got ridiculously sick early on and by the time we limped our way over to Universal it was mainly just a recuperation period while DH went to the parks and played. Club saved us, though, because our appetites were tiny, so the food we purchased outside of Club was almost nothing (relatively). We would do 8 nights again in a heartbeat, because it would have been amazing!
We love atmosphere, seeing, thinking, looking, taking pictures, breathing it all in, and riding and re-re-re-riding. We love to go to a place like Discovery Island on Jurassic Park and just explore for an hour or two. That's our style of touring (we try to do it at WDW, too, but it's still just so big and stressful for us that we're less successful at that). Hence the long stays.
Hope my rambles help in some way?