Ive been getting wanderer x3 and buying boots of mobility, do they stack or should i just buy boots of mobility and not bother with the mastery wanderer

Mobility only,
Movespeed starts to have diminishing returns, I forget at what point though

movespeed hits its massive DR at around 450 MS

The question is, why are you trying to stack movement speed? I think that the items with movement speed boost like Phantom Dancer are beneficial, although the use of PD is limited to certain champs. Mobility boots + a slow item like Rylai's or Frozen Mallet will help you catch up and slow.

just using maokai as a jungler and i find the more movement speed the better i just wanted to know if i have boots of mobility does wanderer become void as in it wont add any speed if i have the boots of mobility

and movement speed was for ganking

Stick with just mobility boots.
Don't forget to build Runic Bulwark/Sunfire Cape/Locket.
Very important. Your support shouldn't be building Runic/Aegis with the new items available. (Locket is good for them too, though)

i always get runic and have started getting locket instead of shurelya's now. is sunfire worth getting iv never bought that item tell me more about it

oh and what u guys think of the item spirit of the elder lizard?