I've owned and sold three Speedmasters over the years. They always sold pretty fast. I try to price them as competitively as possible based on what buyers will see if they scope out the used market. Looks like your's is priced appropriately (low $4Ks) given the miles. I'm not sure buyers care much about the accessories on these, except maybe upgraded (read louder) pipes. Hard to say if you should take the offer since that's a personal thing. You might consider relisting it at $3950 and call it a firm price, if you have the time and if the extra $200 makes a difference. Spring is in the air and buyers are sprouting. Also, I think I saw your bike on
cycletrader and it shows the mileage as 32K rather than 22K. Might want to correct that if it's yours.
Brian W.
PS. I recently was able to ride a "newer" Speedmaster and it's very cool and very different (all in good ways) from the ones I had.