I'm in the middle of building my Avistar ARF, and am estimating that I will finish after about 20 hours total building time. Based on the experiences and challenges I encountered so far...

You might find some bubbles in the Monokote over the fuse and other major assemblies. Don't fret.
- While you can probably get the components replaced, I suggest getting a heat gun and/or iron (w/sock) to tighten things up - no big deal and good practice for your future repairs and kits.

Having the right tools and glues ready to go is key.
- The instruction manual suggests tools that you'll need - I bought and have used them all (and then some!).
- In additiona, a Dremel tool with various cutting and sanding heads will make your trimming work a snap and save lots of time (yes, they do leave a few things to cut/trim away to keep the ARF experience macho enough).

This next experience saved me a lot of headache: before joining your wings, assemble the aileron servo tray (yes, jump slightly ahead), slip your aileron servo into it, place against each wing and eyeball the servo cavity from the side. I found that the servo only by itself would have fit into the cutout on the wingroot rib, but due to the space required by the wires coming out of the servo, a little trimming was in order (more macho-ness to be had).

You will become an expert in the art of glue.
- Buy lots of epoxy mixing cups and brushes (two bags) and don't try to spare them. Mix, glue and chuck.
- Also, you will speed up assembly if, while you are waiting for the glue to dry on a given assembly, you look ahead in the instructions to see if you can put together any other sub components. Use common sense and you won't "paint yourself into a corner".

I learned that thin-CA pretty much sets instantly, so watch out! However, you can use this to your advantage in one area of your assembly:
- When you attach your ailerons and elevators using the fabric hinges, pre-fit everything together, then don't pull the control surface out to access the hinge (like I did on the first try) to apply the CA.
- Instead, use thin-CA, jab the point of the bottle into the crevice as close the hinge as possible (w/o hurting the wing and monokote), then let the thin-CA drip and roll down onto the hinge. The fabric hinge will absorb the thin-CA like a sponge, pulling it off the monokote and drying within a matter of seconds. Wiggle the control surface a little after a five seconds to ensure that nothing is stuck and you are all set. This method will get you nice, narrow gaps between your wing/stablizer and the associated control surfaces - like a pro.

And last...the hardware. It seems that they give you only the exact number of items to complete the kit, so if you lose an item, or something doesn't fit, you'll be stuck. I had problems with the landing gear collars. On almost half of them, the set screw wouldn't screw into the collar (argghhh!). I called Tower Hobbies(where I bought the plane) and they happily sent another bag of hardware corresponding to the parts I needed (so now I'll have some extras of other h/w). Alternatively, I could have just gone down to my LHS - but I was going out of town anyway for a couple of weeks.

On your question about the engine...I deliberated on that, too. Sure, you can put a .46 on it. However, I decided that this is still a TRAINER and that I would treat it as such. The .40 should be fine enough [unless of course you are planning to go head-to-head in all out competition with another trainer and want to devastate them ;o) ] When I want more performance/speed, I'll invest the difference on model #2.

Anyway...hopefully this are a few tips to help you out. I have really enjoyed the experience so far, and am looking forward to completion this weekend. (whoo-hoo!)

Good luck!