I think it would be really hard to say.  If you started at 5 with touch typing QWERTY, that means not only has your cerebellum and motor cortex probably retained extra neurons during growth and development, but the network of synapses are probably like giant tree trunks.  You hands are physically probably well adapted too and if you have never experienced any pain you probably practice good position and posture just like at your piano. I assume you are older than 16 and you brain is  mature. That's a lot to ask any layout to match no matter how much better it may be. Unless you are experiencing fatigue or soreness or pain, you are not likely to be motivated enough to deal with the transition period no matter how much shorter it might be for you than learning something much more different like Dvorak.  The other possible motivation depends on what you call reasonable accuracy at +110 WPM.

If you spend many hours typing each day, the transition is likely to create a great deal of frustration and you might be better off waiting for a vacation or slow period of at least a week or two to try it.   

For a QWERTY athlete such as yourself, it's likely that you may not experience physical issues until your 40's or later.  If that's far off you may be better off just finding things to support your hands and better ergonomic keyboards, etc.

On the other hand, there have been some fast QWERTY typists on here that have reported some pretty phenomenal turnarounds in speed with learning Colemak.  They were not typing quite as fast as you to begin with though.  It does indicate some ancedotal evidence that the same neural networks in your brain for QWERTY are capable to fairly rapid adaptation even in a mature brain to map to something like Colemak that is designed to minimize the changes needed while creating more optimal movement.   That's supported by more recent research that indicates the adult brain is much more adaptable than was once thought a couple of decades ago.  They also do see some drop off in their QWERTY perfomance - though it is not clear whether is temporarily due to learning interference or simply reduced usage and practice.  What is less clear is that whether by having something much closer to QWERTY than Dvorak, you might not be making a tradeoff between easier transition and greater degradation of your prior skill.  It could be that as far as your motor cortex is concerned there is not great enough difference between any layouts not to cause some interference in transition and that there is not real trade off.  It's likely that in time, if you wanted by practice enough to maintain your old skill that you could learn to separate the two and perform both at a high level.  You would seem to be a good candidate for maintaining a skill learned from such an early age.

No one can make any guarantees though.
:-)

Thing is, if you're not a competitive type and you have a setup that works well for you there's much less incentive to improve it than if you don't have a good setup beforehand. Muscle memory aside, there's just so much more to be gained by a QWERTY newbie which means that the cost-benefit curve should be more favourable.

Of course, if it turns out that fast QWERTY typists have a much lesser cost of learning Colemak after all, the argument may change. But I think that may be very individual at any rate.

Well it's upto you, but what I did when I was debating to stick with QWERTY or try an alternative is I first tried Dvorak, but just couldn't learn so many new keys so I gave up on it and tried the next in line, Colemak. After a few days, I've noticed how easy it was to learn the new layout, since only a few change and my accuracy was much better than QWERTY's. So then I decided to stick with Colemak and since then I use it as my only keyboard layout. My QWERTY speed is twice less than before but probably that's because I haven't typed in QWERTY since January. I've encouraged myself not to quit during my initial learning phase by seeing the "Compare" feature of this website, which gave me motivation to ditch QWERTY and and learn Colemak.

BTW, I recommend learning Colemak during a vacation break from school/work, thus less pressure to go back to QWERTY to meet deadlines.

Makes me wonder how it is possible to type 110+ wpm with only 90% accuracy.

Just did a test on "See how fast you can type!", I believe these results in general are 10% too high. Anyway, my QWERTY speed is around 60% (40 WPM) of my initial QWERTY speed (60-70 WPM). My Colemak speed is 40% (90 WPM) more than my original QWERTY.

I've been using Colemak for 9 months, and have literally not typed on any QWERTY keyboards since that. Given this, I believe still keeping 60% of initial speed is not bad.

Okay, I decided to try and get some actual numbers. Results of a one-minute test on about 'enchanted typewriter' from typingtest.com:

Now if I repeated the same story a couple times I could probably boost those numbers just out of familiarity.