As long as everything is functioning and it fits you, I would buy just buy it if you need a bike now and thats all you can afford. How many miles do you need to ride to recover that in saved gas?...not far. In the meantime keep saving for something else. In the end you can can probably resell it for basically the same cost and add that to your new bike fund.
And I don't know what you mean by groups, but for leisurely to moderately fast paced riding, I am sure its fine. There are plenty of groups like that. I think many of the elitists-poseurs above are imagining you taking it out on a A ride hammerfest, which is probably not what you have in mind.