Hey, no problem. $150 is a good bit of difference. I just pulled up the 2006 Stihl price list
here and the difference in MSRP is $120 (479.95 vs 599.95). I don't know if the 30 bucks makes any difference, but at any rate that price list makes for some interesting reading and helps level the playing field with dealers somewhat /forums/images/graemlins/laugh.gif
As for the MS390, I haven't heard anything bad about the saw aside from the fact that it's a bit heavy for its displacement/hp. In fact, though these consumer grade Stihls are often criticized, they're terrific saws when used as they were intended. If you go for the 390 I think you will be very pleased with it, aside from the weight (possibly--but then you're already used to the wt. in the 029/290 so this one will feel like a hotrod)
My current large saw is a Makita DCS6401 that I picked up at Home Depot. I rented it before I bought it just to get a little time on it to see how it performed, and since it performed well I went ahead with the purchase and my rental fee was applied to the purchase price. In some ways this saw is comparable to the MS390, notably in displacement (64) and wt. (13.6 #). However, this is a pro quality saw with a mag. crankcase and it puts out 4.7 hp (mfg specs). For my use, I figured this was a good deal at $205 otd. I do find it a bit heavy in relation to other saws, mainly because a DCS7901 is the same wt. with 15 more cc's.
Now, after blowing all that hot air, I'll finish with this: for your stated usage, if you want a new Stihl, the 390 is a fine choice and should last a very long time. Plus, that extra $150 is enough for a 24" bar and some spare chains, files etc. Let us know when you get that new saw, and give us an update after you put some hrs on it.
/forums/images/graemlins/grin.gif Whew, all that free advice was still cheaper than cuttin a check for $150, and worth every penny you paid for it too.