dawn,
i have used TR many times and any small problems i have had have been dealt with very quickly, and satisfactorily.
the secret to booking through TR, and other companies like them is to get your flights booked first, as this is the bit most prone to change.
once you have confirmation of your flight, then sort out accomodation.
TR do give you a guarantee that if one of their suppliers fails to provide a service you get your money back
for that service only
this is a little help in making you feel more secure about your booking.
although the chances of your holiday going belly up are minimal, it is good practice to have a plan B, so do a bit of research and check out alternative hotels in the resort you have chosen so that if anything does go wrong with the booking at the last minute you have an idea of what alternative hotels are and are not acceptable to you. this saves you any last minute panic, and reduces the chance of you ending up in a hotel miles from where you want to be, or one with really lousy reviews.