We've used Sinclair a number of times over the years (5 times in the past 8 years, to be specific). I feel like they used to be a bit more focused on quality than they are now, but overall, they're still very good.
I contacted them, they knew exactly who I was, so it was good to be remembered. They sent out a sales guy (not the same guy we had always worked with, he had retired), and the guy who came out did a great job of asking the right questions, explaining everything, and gave a quote which he warned was probably a little bit higher than it was going to turn out to be. It turned out, he was right. That was great.
They were great with checking up on us and making sure the details were all good leading up to the day, coordinating the time, etc.
On the day of the move, the crew showed up right on time and moved very fast. It would have taken us a month to pack everything. It took them a couple of hours.
They were very nice and professional during the move, and did a good job unloading everything to generally where we wanted it all. As far as I can tell, nothing important was broken in the process (we have about half the boxes unpacked, the only broken things so far have been a bag of rice that spilled and a box of spaghetti and a box of cheerios which were crushed).
The only issue I can really say I've had this time is how they packed. We've found things from completely different rooms packed together (living room and bathroom, for instance). There were boxes labeled completely wrong. There was a small garbage can which they took the garbage bag out of, tied it up, and packed the garbage. Not the can, just the garbage. There were a number of things like that.
Other than this last time we used them, in the past, we had other guys who definitely moved slower, but seemed to take more care in getting our stuff to where it was going, safely. Before this, we had one lamp break, which they reimbursed us for. That's about the only thing which broke in all those times we moved.
Overall, I'd recommend them.