Yamaha DTXpress/DTXplorer/DTXtreme

i would like to add a double kick pedal to my dtx2. however the 
dtx2 has a very small pad making it impossable to use two 
beaters. this leaves me with a few options, buy another pad and 
have two seperate kick tiggers and two seperate pedals, or get a 
larger pad and use a double pedal.

as ive only been playing drums for a fairly short time, perhaps 
some more experianced people might be able to tell me which 
is the best option

please be kind with me, im a new member.