Interesting thread...
Lets see, IMHO:
1) Hulk steamrolls...
2) Hulk wins in convincing fashion...
3) Hulk gets his first real resistance, but wins...
4) Hulk recieves heavy resistance, but manages to get by...
5) This is where the Hulk stops...
Heres my rational...
Hulk is able to do really well against the Sentinels as they have no ability to adapt to his powerset (unlike the Sentinels comicbook counterparts who killed the Hulk)...
Hulk is faster than them, stronger than them, and is more durable; all in all this is not an ideal matchup for the Sentinels, and its a bigtime challenge for them to deal with Hulk...
On the other hand...
The Sentinels are far more formidible than Ultron Clones and Chitauri (more on the Chitauri in a moment)...
They have much more firepower than either of the above, a data base of powers/abilities they can utilize to help them to better deal with threats, are able to actually effectively coordinate attacks, can fly, can self repair, are pretty agile and strong themselves, and are always (effectively) bloodlusted...
To my knowledge, movie Hulk hasnt shown a significant healing factor and the Chitauri's lesser weapons were able to get the upper hand against the Hulk at one point in time...
Based on that, I think Hulk rampages the Sentinels when its only a few of them, but when they have significant numbers, the Sentinels combat ability increases very significantly and in direct porportion to their numbers...
At number 4 (6 Sentinels) I think they have enough to take some losses before being able to coordinate an effective counterattack...
At number 5 (10 Sentinels), I think there are just too many of them and that they'd overwhelm Hulk, but to a greater degree than the Chitauri did and kill him...
Just my opinion though...