Recommended batteries and amp-hour ratings for DMP systems

[blueman <NOSPAM@xxxxxxxxxx>]

I have an XR200 DMP alarm panel and need to replace the backup batteries which
currently are 2 Genesys (Yuasa) NP7-12 batteries (12v, 7Ah), each fed by
a separate 16.5V 40VA transformer and charging circuit.

The manual says:
"Use sealed lead-acid batteries only: Use the DMP Model 367, 12 VDC 7.0
Ah sealed lead-acid rechargeable battery. Batteries supplied by DMP or
manufactured by Eagle Picher or Yuasa have been tested to ensure proper
charging with DMP products."

However,
1. Is there any reason I couldn't use a 12V battery SLA battery with a
similar form factor but higher Amp-hour rating, particularly since per
DMP each 40VA transformer can support up to 2 batteries? In particular,
there are some batteries that are rated at 9Ah that would still fit in
the existing enclosure (e.g, PowerSonic PS1290 rated at 9Ah
(see: http://www.batterystore.com/Powersonic/PSpdf/PS1290.pdf)

2. More generally, is there any reason that other non-Yusa SLA with
equivalent electrical specs could not be used? (despite the manual
saying the panel was only tested with Eagle Picher & Yuasa) SLA
batteries seem to be pretty comparable and brands like PowerSonic seem
to be reputable. In particular, in addition to looking at the PS1290, I
am also looking at the PS1270 which is a 12V 7Ah battery that has near
identical electrical specs to the Yuasa battery but is a fair bit
lighter and smaller.

Thanks so much for your kind assistance!