Hardware and Fasteners - Hanging my LCD on a concrete wall

I need advice on hanging my 70 lb. tv on a solid concrete wall. I have a few questions:
1. The mount for the TV has two holes and they are only 1 cm wide -- only wide enough for a "medium duty" lag bolt/lead anchor, will this hold my TV?
2. I'm renting and am conscious of not messing up the walls too much, so if I countersink the anchor so that when I leave I can cover it up, will it negatively effect the amount of weight it will hold?
3. Can I use a masonry bit? I've read that a hammer drill is preferred, but I would really rather not have to rent one.
4. I've read lots about tapcon screws on this forum but can't find any info on how much they hold. Are they a good option for me (especially in light of the fact that I can only use 2)?

Thanks in advance for your help.

Welcome to the forums! Depending on the size of the hole in the bracket, I would opt for lead anchor and lag bolt, but more than one. Will it be mounted flush or do you have an angled bracket?

I can and will use two lead anchors and lag bolts. The mount is flush, no angle bracket. One other point that I didn't mention before is that the mount has an arm that can extend out from the wall, so there will be outward and downward force (forgive my non technical description).

Thanks for your help.

No, that is exactly what I was looking for. It changes your force from pure vertical to angular, and it makes a difference. The instructions that come with it should advise the minimal size fastener, and they are probably included, but if not, the same size lag screw and lag shield would hold the load.

Thanks for the advice.

This is the second time I've hung this mount (the first time was into drywall, which I have much more experience with) so any instructions that came with it are long gone. In any event, it didn't come with fasteners (these things never seem to, I think it's a liability issue).

Any input on the masonry drill bit v. hammer drill question?

I think Tapcons are the way to go for something that light. I just went to their website and a 3/16" Tapcon with just 1" embed into concrete has a withdrawal capacity of 600 pounds; 1,090 pounds for 1-1/2" embed.

You can probably get by with a regular drill rather than a hammer drill if you are using Tapcons. If you use Tapcons, I think you have to use their type of drill bit; evidently there's something "magic" about it.

BTW, around here you can rent a hammer drill for $16 for 4 hours.

I agree that Tapcons are probably a good choice, but drilling even two holes with a Tapcon bit can be a PITA with a standard drill. I just did 12 3/16" Tapcons with 14v DeWalt drill/driver because my SIL still has my hammer drill I loaned him 6 months ago. :mad:
Ask around, one of your friends/neighbors may have a hammer drill you can borrow.
I have to say that if it were my big screen HDTV I would probably go with either lags or studs set in anchor cement. Overkill, but those TV's are expensive.