Me and my girlfriend stayed in this hotel 2 years ago (during euro 2004) on a H/B Package. From the outside this hotel is nothing to look at especially when you see all the other nice hotels on the drive to yours as the other holiday makers are being dropped of before you. Most of them had big gates you had to drive through and big long drives to the front of the hotel, so when we had to cross a busy road at 9pm on our arrival we thought "OH NO".
From memory there are 2 buildings and in each 3 floors. The swimming pool is of average size and gets the sun all day. We got a room on the 3rd floor in the corner at the back (not the one facing the main road) and it was huge with a balcony, It had a good size bathroom, kitchen, fridge and working air-con. I believe the 1st floor has no balconies only the 2nd and 3rd floors. The hotel is very clean, food is fresh and varied and I found all the staff to be very pleasant and helpful. There are 2 bars in the hotel and you can sit outside the one downstairs at the tables and chairs.There is also a wee local shop selling essentials and one sells knick knacks and in it's upstairs it also sells rugs etc.
When we were leaving we had to book a room as our flight was late in the evening and this is where we saw the bad side of the hotel as we were only using it for 5 hours or so it was ok but to stay in this for a week or more, I would have complained, It was tiny and faced onto the main road and there was a loud buzzing/humming coming from the roof (maybe a generator). so noise would have been a problem in this part of the building from the roof and the main road.
You are only 5mins from PEK and 10 from sousse by Taxi, 2-3 dinar at most. The beach is less than a 1/4 of a mile from the hotel and was tidy and spacious. Outside the hotel and down to your right is street that has 2 or 3 wee restaurants ( The Italian one is nice, we ate there twice, try the mint tea).
Like you say if your only there for R+R and only need someplace to camp for the night, the sinbad was really OK in my book, You dont have the hassle of PEK's shops all the time if that doesnt interest you. There was no real entertainment at this hotel. hope you get some useful info from this and sorry for it being so long