Did you do a search in these forums on PCT? How about checking their ResellerRatings?
If you had done either of these, I don't think you would be questioning whether or not to buy from PCT.
As to buying from a reseller vs direct from SAGER, it obviously depends on the reseller. A bad reseller is a bad reseller and will make the transaction a bad one no matter what. But if you buy through a reputable reseller such as PCT (and there are others) there's no question its a much better deal than direct from SAGER. SAGER gives the resellers a good deal so they can often price SAGER, why?, so SAGER doesn't have to deal with all of us bozos. They'd much rather just build computers which is what they do best.
One of the main reasons for going through a reseller, other than the price is usually better, is if you do have a problem with SAGER would you rather deal with them one on one (one small individual against a moderately sized manufacturer) by yourself or would you rather have a dealer (who buys a large number of machines from SAGER and most likely has a good relationship with the people that count at SAGER) on your side helping you out?
And please don't assume that SAGER is likely to be difficult to deal with, after 6 machines I am still very sold on the company. I bought the first two directly and had no complaints. I have bought through three different resellers since and also have no complaints.
There is also the matter that you get another source of assistance and information when you deal with a reseller. Another helping hand. Some may not be all that helpful but all the ones I've dealt with (including PCT) have been most helpful.