I went twice to Tenggol Island Beach Resort - once in June'10 and another in August'10

Main attraction is diving.
Divers are quite basic, we need good dive center, divemaster, good food, and bare essentials for accomodation.
Boatmen are good! Divemaster Robin is a funny man!

Beware of sandflies - if you have sensitive skin like me, make sure you get ready with anti-histamine tabs ( like Zyrtex), alcohol swabs and antiseptic cream (if you are bitten by sandflies - clean the wound and apply - it worked more effectively).
Make sure you have your insects repellent, i recommend Mosi-Guard.

Beach and the seawater are amazingly white, crystal clear. Really loving the view.

Good things: Hot shower, air condition, nice staff, good food, beatiful island and beach.

Our bungalow was situated in the far back of the beach and didn't have any windows. (!) There was also a loud noice inside the bungalow from the electricity generator at night. One moth earlier they had replaced their beach front bungalows with new ones far away from the beach instead. It's very stange. The only good bungalow of the resort with a beach view was for the staff. So the staff lived better than the guests.

When you read about diving at Tenggol it says "Whale shark, manta rays and lots of shark". Turns out non of these creatures has been spotted outside the island since 2009. Two years back you could see the whale shark just outside the bay on every dive, but seems like we came too late.
We were also unhappy with our dive guide. He was a nice and friendly guy, but not a very dedicated guide. Over all our diving experience was quiet poor. We also heard huge bangs every night and fear that it might have been dynamite fishing close to the island.

Snorkeling in the bay is quiet good, we sawe turtles, great barraquda and some nice corals, but unfortunately most corals dead.

There are two other resorts on the beach. Tenggol Island Resort seems nice from a distance, but is quiet worned out when you get closer. The third place didn't seem that good either. Unfortunately I probably wouldn't recomend anyone to go to Tenggol, even though this island beautiful and has great potential.

My experience in this place was not so nice, you can stay if you are confortable to stay in a Camp, My "Bungalow" was made in a very tiny steel, with Aircon, but no light, unless you open the solid windows or door, but there is mosquitos and sandflies.
For sure the value for money is'nt appropriate.
You will have very nice dives in the Diving center, The staff (not the manager) is very helpful and nice. Expecially Robin the Divemaster, but I hope for him to work elsewere, He is very helpful and nice. Pay attention not to lose him during your Dives ;)
The manager is a strange guy, probably will tell you to meet him at the reception of your hotel in KL to collect the money upfront, there will be no refound if you will leave earlier, So don't pay everithing upfront,
The Island is very little, and for sure you do'nt want to stay longer then 3 days, even if there is a little chance to see the Whale shark.
We didn't seeit :(
If you wanna visit Tenggol it was sadly the only "resort" thet I was capable of find online, but in the island there are 2 more. Wich are defenitely better.

Our family, two adults and a child, stayed here for three nights in July. I recommend a trip here if your primary interests are snorkelling, diving, or hanging out on a relatively small, but empty, beach. The rooms are very basic and small, but feature excellent AC and hot water. Electricity is on by about 6 p.m. and stays on until early morning. This is not a place to hang out in your room. The beach faces the mainland in the west, and sitting on the dining veranda offers a view of a different sunset every night. The food was quite good for this setting. Bear in mind that this place is isolated and absolutely everything has to be transported there by boat by the resort staff. Our viz was variable and so-so--around 10-12 meters--but we were diving around full moon and you might have better conditions at other times. We did six dives, which included one excellent dive. The others ranged from okay to good. This area is evidently suitable for deeper dives. Snorkelling in the bay is outstanding, but the water can be a bit rough outside the edges. I saw turtles and even a group of three large Napoleon wrasses. Our DM, Robin, was okay, but my impression is that he didn't really try that hard to bring us to the best spots. All spots except for the best one were close to the resort, but the dive map showed many others located further away. Without a better understanding of the sites, though, I can't judge the diving potential here with much accuracy. Sand flies were a bit of a problem, but repellant kept them away. I also apparently fed some bedbugs on the last night of our stay. Staff were honest and generally helpful. This property is under Malaysian-Chinese management.