Hi doc, I wanted to know which is the best...

regarding your main questions :
product to better sexual performance without side effects ?
there are medications to treat erectile dysfunction if you are suffer from that medical condtion , and its advised to be taken after consulting doctor , but if advised against using it if you are healthy as it may cause pyschological dependance which means you wont be able to perform sexual acitivty without using it although you didnt need it in the first place 
- they also have side effects 
- there are supplements that may increase sexual ability and performance on the longer course , and their side effects are usually light or dont appear 
regarding increase penis size :
no product or medication can increase penis size 
medications of erectile dysfunction :
1. Sildenafil ( viagra )
2. Vardenafil ( levitra )
3. tadalafil (cialis )
Those mediction have side effects :
1. headache 
2. muscles pain
3. diarrhea
4. facial flushing 
5. nasal congestion 
6. heartburn
products and suppliments to increase sexual ability :
1. multimaka 
2. alpha testo
3. royal jelly 
vitamins and food the increase your sexual ability :
- vitamins :
1. vitamin E
2. vitamin C 
3. vitamin B12
4. vitamin D
5. selenium
- food :
1. red meat
2. eggs and milk products 
3. almond and walnut 
4. sea food and oysters
5. mashrooms