If i understand correctly , your 2 BGP router are connected to 2 ISP router with 1 EBGP session on both the router.
To do load balancing for the incoming traffic you could use AS path prepenad and MED,but i will suggest to use AS path prepend since MED is a weak metrick since it come below AS is BGP path selection attributes.
in this case being the connections to same ISP/AS MED may be an acceptable tool in Vinoth's scenario.
With selective prepending is possible to divide IP subnets in two subsets one advertised without prepending by R1 and with prepending by R2; the opposite happens for the other subset of routes: R2 advertises them without prepending and R1 with prepending.
This may be a better solution if your border routers are in different sites to give preference to site specific routes.
>> What are the drawback of using AS prepending instead of MED ?
its effect extends over the neighboring ISP.
MED is not propagated beyond it.
This may be a desired result when you want to be sure that traffic destined to subset1 of customer routes should come back on R1 for some reasons (symmetrical paths or site specific routes for example)
if both MED and AS Path prepending are set as you noted the second is considered first in BGP path selection hierarchy.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...