Has anyone stayed in the Kilmartin Glen area? Any thoughts on this? Thank you :)
I stayed in Lochgilphead and I would not recommend it. It may have been just a bad hotel choice, But I wished I had looked harder. Here is the Undiscovered Scotland page. The place I stayed in was inexpensive, but it had warts. It's been a while so I can't give you the hotel. I wasn't unsafe, just uncomfortable. Just check reviews. I am sure that there are some good places. The location re Kilmartin Glen is handy.
If you're willing to be about half an hour away, I can highly recommend Brambles in Inveraray. We enjoyed it so much our first time that we made a point of returning the following year. Besides the nice things to see & do in Inveraray itself, on your way south toward Lochgilphead there's the unique Auchindrain Township open-air museum; there's also horseback riding at Argyll Adventure.
If, OTOH, you want to be further south on the peninsula, the Stonefield Castle Hotel just outside Tarbert is also very nice. As you'd expect with a castle hotel, it's rather formal (but not too) and a little in need of maintenance.
The tiny village of Kilmartin has a couple of B&Bs, if I remember correctly. If you're going there to see the cairns, make sure to buy the map for a pound or so in the tiny museum in the village. They are not well signposted, so without the map you may very well drive right past them.
I'll second Stonefield Castle. That's where I was headed after the minor disaster at Lochgilphead! I really enjoyed my time there. The town is nice too.