Age Old Dilemma Options

[kalki2000]

Hi all,
I am new to this forum. I am a recent convert/ believer in Mac and currently have powerbook G4 1.5 512/external firewire400 HD.
I was earlier using echoaudio's layla 24/96 (pci version) on my windows PC with cubase 5.1

So it has been a while since really needed to upgrade my system.

SInce MIDI implementation and the quality of plugins have improved, I am now more inclined to upgrade my software but also to convert to a mac platform. Cubase per se from what I have read in other forums has latency issues.

I also happen to have Kurzweil 2500xs and motif ES. I plan to upgrade to mlan so that I can record 16 audiotracks from motif plus 2 steoreo tracks from kurzweil simultaneously on to my external hard drive thro' powerbook. I will not be using many effects while recording the tracks. They will come in only during the mix/master stage.
I will also use 1-5(max) instances of Akai samples loaded onto software sampler ( need to get one, if not included with sequencer software) and Groove agent VSTi as a drum module.

The beat detection engine of DP4.5 appeals to me. however it seems that this function can also be accomplished with cubase and logic. please correct me if I am wrong. So here comes one of the most often asked questions,

between logicexpress, logicpro, cubasesx3, DP4.5 which would best suit my needs?

I understand budget is everything. But my other issues are latency, compatibility with echo layla laptop version, able to use mlan on powerbook with host sequencer without CPU overload and finally something that can also handle groove agent VSTi without latency issues even if I have to use 3rd party plugins for AU. I have not had the opportunity to play around with these sequencers/software. If anybody has a similar setup or have had the experience/ suggestions I greatly appreciate your input. Thanks in advance. Sorry for this long post. Thought I should clearly state what I am looking for