I'll give you two pieces of advice, my opinion only, of course

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1. I briefly rode two-wheelers, unlicensed, nearly 20 years ago during my college years. I enjoyed them, but I never quite felt safe on them. I know that I needed more time on them, more patience with myself, but the learning curve for street riding can be steep, and very unforgiving (wish I had enjoyed the luxury of dirtbiking, but couldn't easily do that in city-living).
Fast forward to this year, I figured I'd finally go and get my motorcycle license. Signed up for the MSF two-wheeler course to get my license, but on a lark I also signed up for an MSF three-wheeler course. Part of me figured I might consider a trike-- I dug some of the Harley aftermarket conversions, and thought I could see myself on one.
While I knew about the Spyder, I hadn't really considered it. At first glance the styling wasn't my cup of tea, and it was such a new product, I figured it'd be too sketchy mechanically for the serious price.
Then, lo and behold, my MSF trike class was scheduled to occur before the two-wheeler course, and the company that offered it here in Virginia used Spyder RTs and RSs to teach the class.
(I did a write up of my experience here:
http://www.spyderlovers.com/forums/showthread.php?t=27303)
Bottom line: I had a blast.
Even after the class, however, I wasn't completely sold on the Spyder, mostly because it was more money than I wanted to spend this year. But it stuck in my head, and as I got closer to my two-wheeler course, I kept telling myself, "Why bother? You know you want the Spyder, so go get the Spyder, you dummy."
Which is exactly what I did. And I'm happy as heck that I did. Sure, it wasn't cheap, but I've had no serious mechanical problems (granted, I still have low mileage, <2000 miles). And I have tons of fun riding it.
More importantly... MOST importantly, I feel safe on it, in a way that I never felt on bikes.
A motorcycle has a steep learning curve, there are a million things to remember while riding one. Once you get the hang of it, that curve doesn't really lessen, however--- you just *think* that it lessens. Meaning, even an experienced motorcycle rider still has to occupy their attention span with all kinds of concerns even when just riding to the corner store: available traction, lean angles, sand and gravel and potholes, cornering lines, front vs. rear braking, etc., etc., etc.
And that's all before you worry about all the traffic around you trying to kill you.
For many folks, they're comfortable with that much effort; they enjoy that level of involvement with their machine. And let's face it, when it all comes together perfectly, motorcycles are very, very fun. :doorag:
For me, however, I just find the Spyder removes a lot of the anxiety that comes with any two wheeler, which allows me to use my limited attention span focused more on the cars around me than on the condition of the road ahead, or the physics of my handling & braking. Yes, even the Spyder is still FAR more involved than driving a car around the block, but it is nowhere near as taxing as a motorcycle, particularly in heavy urban traffic (a.k.a., the Death Race 2000 that is D.C.).
Plus, again... what fun. :2thumbs:
2.
As a general rule, I agree with the professional motorcycle educator consensus: your first bike should be a small bike.
The Dyna Glide is a beautiful bike, but it's not for a beginner; personally, I'm hesitant to even consider it a good *second* bike for most folks.
I second the recommendation to find a dealer will let you test ride the Spyder, which for its weight and power is a lot less intimidating to a comparable bike (you can't drop it on your leg, for one!).
But if you find the Spyder isn't for you, and you'd still like to use the Dyna Glide, I'd suggest shopping for an "interim" used bike, in the 250cc+ range (600-700cc max, if you stick to forgiving cruisers like the Suzuki Savage or Kawasaki Vulcan). I guarantee that you'll feel more comfortable on it, you'll get the hang of all the basics much faster, you'll be less likely to get into serious trouble when you screw up (and we new riders always screw up), and best of all, after a few months of practice, you'll be able to sell it for pretty much what you paid for it, i.e. it really will cost you nothing.
This way, you'll be able to make an informed decision on whether you want to stick with two wheels and keep the Dyna Glide, or whether you want to go in the Spyder direction.
Good luck, and safe riding!